Changes in immunological potential between juvenile and presenile in rabbit

To investigate the relationship between immunological potential and advance of age, patterns of humoral immune response in different aged rabbits were compared. In the primary response, the appearance of total antibody and the arrival to its peak level were retarded by advance of age. On the other hand, the appearance fo IgG antibody was the earliest in young and young adult rabbits though the arrival to its peak level was the latest. The disappearance of total and IgG antibodies was earlier in older and immature animals. In the secondary response, the reincrease of total antibody occured on the same day regardless of the age, but the older were the rabbits, the earlier was the reincrease of IgG antibody and also the arrival to the peak level of both antibodies. In the primary and the secondary responses, the maximal titers of both antibodies were the highest in young and young adult groups. From these results, the exact comparison of immunological potentials in rabbits of different age is possible only by the comparison of patterns of immune responses together with their intensity.